Lazaro Mendez, know to his fans as DJ Laz, is the owner of the 40 foot vessel dubbed "Off The Air" and was operating it at the time of the accident. (Source: CBS4)

KEY BISCAYNE (CBSMiami) – A popular South Florida radio personality was behind the wheel of a boat involved in a deadly accident over the weekend in Key Biscayne.

The Florida Fish and Wildlife Conservation Commission confirmed that Lazaro Mendez, know to his fans as DJ Laz, is the owner of the 40 foot vessel dubbed “Off The Air” and was operating it at the time of the accident. DJ Laz said he said he named the boat in a self-deprecating reference to his losing his job as the morning host on Power 96 after 22 years and later being let go by 106.7 FM.

On Sunday, several people were helping to push the boat off the sandbar at Nixon Beach when 23-year old Ernesto Hernandez pitched in to help.

Hernandez’s family said it’s not surprising he would volunteer to lend a hand.

“He’s just a very giving person,” said Hernandez’s cousin Michael Gonzalez. “He had a heart of gold. Abig teddy bear is really what he was. He’s huge in size and his heart is just as big.”

Relatives said the man they called “Ernie” was a personal bodyguard who graduated from the police academy.

“The Hernandez family has had it’s brightest light unnecessarily extinguished before his time,” Gonzalez said.

The medical examiner listed his cause of death as “multiple chop wounds”.

Law enforcement boats were already gathered in the area off Nixon Beach to patrol the crowds Sunday when they rushed in to help Hernandez.

“The rescue pulled up next to us with a gentleman in real bad shape. He was covered up. They were pumping him,” said Frank Alonso, who was out boating.

“They put him in the rescue, the helicopter came and took off,” added Werner Velasquez.

Pino described Mendez as being distraught at the scene and “very sympathetic” to the family of the man who died.

On Monday, Mendez posted this statement on his Facebook and Twitter pages:

“I am incredibly distraught over the unfortunate accident that occurred yesterday at Nixon Beach. My family and I send our heartfelt condolences to the family and friends of Ernesto Hernandez; they are in our thoughts and prayers. I have and will continue to cooperate fully with investigators during this tragic time.” -Lazaro Mendez

Investigators are trying to determine exactly how the incident happened. Pino said Mendez has “cooperated fully” in the investigation.

“Our investigators are going to look at whether alcohol played a role, carelessness, recklessness. All those things will be looked into to see if we should press charges against the operator of the vessel,” said Pino.

Pino had told CBS4 News DJ Laz had provided a blood sample to allow investigators to check for drugs or alcohol in his system. Late Monday Pino reversed himself, saying there was no blood sample or breathalyzer taken of Lazaro Mendez, because there was no “probable cause,” evidence of impairment to justify it.

Pino says investigators observed “no blood shot eyes, slurred speech or unsteady movement” to suggest DJ Laz was impaired. Still, they called state attorney who said they couldn’t compel a blood or breath test without probable cause. They still asked him to give a voluntary breathalyzer and he refused.

The victim’s sister, Mildren Hernandez, was overcome with tears during a press conference Monday, but managed to make an emotional request to witnesses.

“If you have any information, please send it to us,” she said.

They hope pictures or video of the scene will help shed light on exactly what went wrong.

Lauren Pastrana is the co-anchor of CBS4 News This Morning airing Monday-Friday, from 5 to 7 AM. She joined CBS Miami in April 2012 as a reporter. She is an Emmy nominated, multimedia journalist with experience in television, radio and web-based ...